/*
 * Copyright (C) 2009 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#include <assert.h>
#include <math.h>
#include <stdio.h>
#include <string.h>
#include "../include/lpicache.h"
#include "../include/matrixsearch.h"
#include "../include/mystdlib.h"
#include "../include/ngram.h"
#include "../include/userdict.h"

#define LOG_TAG "MatrixSearch" // 这个是自定义的LOG的标识
//用于打印debug级别的log信息
#define LOGD(...) __android_log_print(ANDROID_LOG_DEBUG, LOG_TAG, __VA_ARGS__)
namespace ime_pinyin {

#define PRUMING_SCORE 8000.0

    MatrixSearch::MatrixSearch() {
        inited_ = false;
        spl_trie_ = SpellingTrie::get_cpinstance();

        reset_pointers_to_null();

        pys_decoded_len_ = 0;
        mtrx_nd_pool_used_ = 0;
        dmi_pool_used_ = 0;
        xi_an_enabled_ = false;
        dmi_c_phrase_ = false;

        assert(kMaxSearchSteps > 0);
        max_sps_len_ = kMaxSearchSteps - 1;
        max_hzs_len_ = kMaxSearchSteps;
    }

    MatrixSearch::~MatrixSearch() {
        free_resource();
    }

    void MatrixSearch::reset_pointers_to_null() {
        dict_trie_ = NULL;
        user_dict_ = NULL;
        spl_parser_ = NULL;

        share_buf_ = NULL;

        // The following four buffers are used for decoding, and they are based on
        // share_buf_, no need to delete them.
        mtrx_nd_pool_ = NULL;
        dmi_pool_ = NULL;
        matrix_ = NULL;
        dep_ = NULL;

        // Based on share_buf_, no need to delete them.
        npre_items_ = NULL;
    }

    bool MatrixSearch::alloc_resource() {
        free_resource();

        dict_trie_ = new DictTrie();
        user_dict_ = static_cast<AtomDictBase *>(new UserDict());
        spl_parser_ = new SpellingParser();

        size_t mtrx_nd_size = sizeof(MatrixNode) * kMtrxNdPoolSize;
        mtrx_nd_size = align_to_size_t(mtrx_nd_size) / sizeof(size_t);
        size_t dmi_size = sizeof(DictMatchInfo) * kDmiPoolSize;
        dmi_size = align_to_size_t(dmi_size) / sizeof(size_t);
        size_t matrix_size = sizeof(MatrixRow) * kMaxRowNum;
        matrix_size = align_to_size_t(matrix_size) / sizeof(size_t);
        size_t dep_size = sizeof(DictExtPara);
        dep_size = align_to_size_t(dep_size) / sizeof(size_t);

        // share_buf's size is determined by the buffers for search.
        share_buf_ = new size_t[mtrx_nd_size + dmi_size + matrix_size + dep_size];

        if (NULL == dict_trie_ || NULL == user_dict_ || NULL == spl_parser_ ||
            NULL == share_buf_)
            return false;

        // The buffers for search are based on the share buffer
        mtrx_nd_pool_ = reinterpret_cast<MatrixNode *>(share_buf_);
        dmi_pool_ = reinterpret_cast<DictMatchInfo *>(share_buf_ + mtrx_nd_size);
        matrix_ = reinterpret_cast<MatrixRow *>(share_buf_ + mtrx_nd_size + dmi_size);
        dep_ = reinterpret_cast<DictExtPara *>
        (share_buf_ + mtrx_nd_size + dmi_size + matrix_size);

        // The prediction buffer is also based on the share buffer.
        npre_items_ = reinterpret_cast<NPredictItem *>(share_buf_);
        npre_items_len_ = (mtrx_nd_size + dmi_size + matrix_size + dep_size) *
                          sizeof(size_t) / sizeof(NPredictItem);
        return true;
    }

    void MatrixSearch::free_resource() {
        if (NULL != dict_trie_)
            delete dict_trie_;

        if (NULL != user_dict_)
            delete user_dict_;

        if (NULL != spl_parser_)
            delete spl_parser_;

        if (NULL != share_buf_)
            delete[] share_buf_;

        reset_pointers_to_null();
    }

    bool MatrixSearch::init(const char *fn_sys_dict, const char *fn_usr_dict) {
        if (NULL == fn_sys_dict || NULL == fn_usr_dict)
            return false;

        if (!alloc_resource())
            return false;

        if (!dict_trie_->load_dict(fn_sys_dict, 1, kSysDictIdEnd))
            return false;

        // If engine fails to load the user dictionary, reset the user dictionary
        // to NULL.
        if (!user_dict_->load_dict(fn_usr_dict, kUserDictIdStart, kUserDictIdEnd)) {
            delete user_dict_;
            user_dict_ = NULL;
        } else {
            user_dict_->set_total_lemma_count_of_others(NGram::kSysDictTotalFreq);
        }

        reset_search0();

        inited_ = true;
        return true;
    }

    bool MatrixSearch::init_fd(int sys_fd, long start_offset, long length,
                               const char *fn_usr_dict) {
        if (NULL == fn_usr_dict)
            return false;

        if (!alloc_resource())
            return false;

        if (!dict_trie_->load_dict_fd(sys_fd, start_offset, length, 1, kSysDictIdEnd))
            return false;

        if (!user_dict_->load_dict(fn_usr_dict, kUserDictIdStart, kUserDictIdEnd)) {
            delete user_dict_;
            user_dict_ = NULL;
        } else {
            user_dict_->set_total_lemma_count_of_others(NGram::kSysDictTotalFreq);
        }

        reset_search0();

        inited_ = true;
        return true;
    }

    void MatrixSearch::set_max_lens(size_t max_sps_len, size_t max_hzs_len) {
        if (0 != max_sps_len)
            max_sps_len_ = max_sps_len;
        if (0 != max_hzs_len)
            max_hzs_len_ = max_hzs_len;
    }

    void MatrixSearch::close() {
        flush_cache();
        free_resource();
        inited_ = false;
    }

    void MatrixSearch::flush_cache() {
        if (NULL != user_dict_)
            user_dict_->flush_cache();
    }

    void MatrixSearch::set_xi_an_switch(bool xi_an_enabled) {
        xi_an_enabled_ = xi_an_enabled;
    }

    bool MatrixSearch::get_xi_an_switch() {
        return xi_an_enabled_;
    }

    bool MatrixSearch::reset_search() {
        if (!inited_)
            return false;
        return reset_search0();
    }

    bool MatrixSearch::reset_search0() {
        if (!inited_)
            return false;

        pys_decoded_len_ = 0;
        mtrx_nd_pool_used_ = 0;
        dmi_pool_used_ = 0;

        // Get a MatrixNode from the pool
        matrix_[0].mtrx_nd_pos = mtrx_nd_pool_used_;
        matrix_[0].mtrx_nd_num = 1;
        mtrx_nd_pool_used_ += 1;

        // Update the node, and make it to be a starting node
        MatrixNode *node = mtrx_nd_pool_ + matrix_[0].mtrx_nd_pos;
        node->id = 0;
        node->score = 0;
        node->from = NULL;
        node->step = 0;
        node->dmi_fr = (PoolPosType) -1;

        matrix_[0].dmi_pos = 0;
        matrix_[0].dmi_num = 0;
        matrix_[0].dmi_has_full_id = 1;
        matrix_[0].mtrx_nd_fixed = node;

        lma_start_[0] = 0;
        fixed_lmas_ = 0;
        spl_start_[0] = 0;
        fixed_hzs_ = 0;

        dict_trie_->reset_milestones(0, 0);
        if (NULL != user_dict_)
            user_dict_->reset_milestones(0, 0);

        return true;
    }

    bool MatrixSearch::reset_search(size_t ch_pos, bool clear_fixed_this_step,
                                    bool clear_dmi_this_step,
                                    bool clear_mtrx_this_step) {
        if (!inited_ || ch_pos > pys_decoded_len_ || ch_pos >= kMaxRowNum)
            return false;

        if (0 == ch_pos) {
            reset_search0();
        } else {
            // Prepare mile stones of this step to clear.
            MileStoneHandle *dict_handles_to_clear = NULL;
            if (clear_dmi_this_step && matrix_[ch_pos].dmi_num > 0) {
                dict_handles_to_clear = dmi_pool_[matrix_[ch_pos].dmi_pos].dict_handles;
            }

            // If there are more steps, and this step is not allowed to clear, find
            // milestones of next step.
            if (pys_decoded_len_ > ch_pos && !clear_dmi_this_step) {
                dict_handles_to_clear = NULL;
                if (matrix_[ch_pos + 1].dmi_num > 0) {
                    dict_handles_to_clear =
                            dmi_pool_[matrix_[ch_pos + 1].dmi_pos].dict_handles;
                }
            }

            if (NULL != dict_handles_to_clear) {
                dict_trie_->reset_milestones(ch_pos, dict_handles_to_clear[0]);
                if (NULL != user_dict_)
                    user_dict_->reset_milestones(ch_pos, dict_handles_to_clear[1]);
            }

            pys_decoded_len_ = ch_pos;

            if (clear_dmi_this_step) {
                dmi_pool_used_ = matrix_[ch_pos - 1].dmi_pos
                                 + matrix_[ch_pos - 1].dmi_num;
                matrix_[ch_pos].dmi_num = 0;
            } else {
                dmi_pool_used_ = matrix_[ch_pos].dmi_pos + matrix_[ch_pos].dmi_num;
            }

            if (clear_mtrx_this_step) {
                mtrx_nd_pool_used_ = matrix_[ch_pos - 1].mtrx_nd_pos
                                     + matrix_[ch_pos - 1].mtrx_nd_num;
                matrix_[ch_pos].mtrx_nd_num = 0;
            } else {
                mtrx_nd_pool_used_ = matrix_[ch_pos].mtrx_nd_pos
                                     + matrix_[ch_pos].mtrx_nd_num;
            }

            // Modify fixed_hzs_
            if (fixed_hzs_ > 0 &&
                ((kLemmaIdComposing != lma_id_[0]) ||
                 (kLemmaIdComposing == lma_id_[0] &&
                  spl_start_[c_phrase_.length] <= ch_pos))) {
                size_t fixed_ch_pos = ch_pos;
                if (clear_fixed_this_step)
                    fixed_ch_pos = fixed_ch_pos > 0 ? fixed_ch_pos - 1 : 0;
                while (NULL == matrix_[fixed_ch_pos].mtrx_nd_fixed && fixed_ch_pos > 0)
                    fixed_ch_pos--;

                fixed_lmas_ = 0;
                fixed_hzs_ = 0;
                if (fixed_ch_pos > 0) {
                    while (spl_start_[fixed_hzs_] < fixed_ch_pos)
                        fixed_hzs_++;
                    assert(spl_start_[fixed_hzs_] == fixed_ch_pos);

                    while (lma_start_[fixed_lmas_] < fixed_hzs_)
                        fixed_lmas_++;
                    assert(lma_start_[fixed_lmas_] == fixed_hzs_);
                }

                // Re-search the Pinyin string for the unlocked lemma
                // which was previously fixed.
                //
                // Prepare mile stones of this step to clear.
                MileStoneHandle *dict_handles_to_clear = NULL;
                if (clear_dmi_this_step && ch_pos == fixed_ch_pos &&
                    matrix_[fixed_ch_pos].dmi_num > 0) {
                    dict_handles_to_clear = dmi_pool_[matrix_[fixed_ch_pos].dmi_pos].dict_handles;
                }

                // If there are more steps, and this step is not allowed to clear, find
                // milestones of next step.
                if (pys_decoded_len_ > fixed_ch_pos && !clear_dmi_this_step) {
                    dict_handles_to_clear = NULL;
                    if (matrix_[fixed_ch_pos + 1].dmi_num > 0) {
                        dict_handles_to_clear =
                                dmi_pool_[matrix_[fixed_ch_pos + 1].dmi_pos].dict_handles;
                    }
                }

                if (NULL != dict_handles_to_clear) {
                    dict_trie_->reset_milestones(fixed_ch_pos, dict_handles_to_clear[0]);
                    if (NULL != user_dict_)
                        user_dict_->reset_milestones(fixed_ch_pos, dict_handles_to_clear[1]);
                }


                pys_decoded_len_ = fixed_ch_pos;

                if (clear_dmi_this_step && ch_pos == fixed_ch_pos) {
                    dmi_pool_used_ = matrix_[fixed_ch_pos - 1].dmi_pos
                                     + matrix_[fixed_ch_pos - 1].dmi_num;
                    matrix_[fixed_ch_pos].dmi_num = 0;
                } else {
                    dmi_pool_used_ = matrix_[fixed_ch_pos].dmi_pos +
                                     matrix_[fixed_ch_pos].dmi_num;
                }

                if (clear_mtrx_this_step && ch_pos == fixed_ch_pos) {
                    mtrx_nd_pool_used_ = matrix_[fixed_ch_pos - 1].mtrx_nd_pos
                                         + matrix_[fixed_ch_pos - 1].mtrx_nd_num;
                    matrix_[fixed_ch_pos].mtrx_nd_num = 0;
                } else {
                    mtrx_nd_pool_used_ = matrix_[fixed_ch_pos].mtrx_nd_pos
                                         + matrix_[fixed_ch_pos].mtrx_nd_num;
                }

                for (uint16 re_pos = fixed_ch_pos; re_pos < ch_pos; re_pos++) {
                    add_char(pys_[re_pos]);
                }
            } else if (fixed_hzs_ > 0 && kLemmaIdComposing == lma_id_[0]) {
                for (uint16 subpos = 0; subpos < c_phrase_.sublma_num; subpos++) {
                    uint16 splpos_begin = c_phrase_.sublma_start[subpos];
                    uint16 splpos_end = c_phrase_.sublma_start[subpos + 1];
                    for (uint16 splpos = splpos_begin; splpos < splpos_end; splpos++) {
                        // If ch_pos is in this spelling
                        uint16 spl_start = c_phrase_.spl_start[splpos];
                        uint16 spl_end = c_phrase_.spl_start[splpos + 1];
                        if (ch_pos >= spl_start && ch_pos < spl_end) {
                            // Clear everything after this position
                            c_phrase_.chn_str[splpos] = static_cast<char16>('\0');
                            c_phrase_.sublma_start[subpos + 1] = splpos;
                            c_phrase_.sublma_num = subpos + 1;
                            c_phrase_.length = splpos;

                            if (splpos == splpos_begin) {
                                c_phrase_.sublma_num = subpos;
                            }
                        }
                    }
                }

                // Extend the composing phrase.
                reset_search0();
                dmi_c_phrase_ = true;
                uint16 c_py_pos = 0;
                while (c_py_pos < spl_start_[c_phrase_.length]) {
                    bool b_ac_tmp = add_char(pys_[c_py_pos]);
                    assert(b_ac_tmp);
                    c_py_pos++;
                }
                dmi_c_phrase_ = false;

                lma_id_num_ = 1;
                fixed_lmas_ = 1;
                fixed_lmas_no1_[0] = 0;  // A composing string is always modified.
                fixed_hzs_ = c_phrase_.length;
                lma_start_[1] = fixed_hzs_;
                lma_id_[0] = kLemmaIdComposing;
                matrix_[spl_start_[fixed_hzs_]].mtrx_nd_fixed = mtrx_nd_pool_ +
                                                                matrix_[spl_start_[fixed_hzs_]].mtrx_nd_pos;
            }
        }

        return true;
    }

    void MatrixSearch::del_in_pys(size_t start, size_t len) {
        while (start < kMaxRowNum - len && '\0' != pys_[start]) {
            pys_[start] = pys_[start + len];
            start++;
        }
    }

    size_t MatrixSearch::search(const char *py, size_t py_len) {
        if (!inited_ || NULL == py)
            return 0;

        // If the search Pinyin string is too long, it will be truncated.
        if (py_len > kMaxRowNum - 1)
            py_len = kMaxRowNum - 1;

        // Compare the new string with the previous one. Find their prefix to
        // increase search efficiency.
        size_t ch_pos = 0;
        for (ch_pos = 0; ch_pos < pys_decoded_len_; ch_pos++) {
            if ('\0' == py[ch_pos] || py[ch_pos] != pys_[ch_pos])
                break;
        }

        bool clear_fix = true;
        if (ch_pos == pys_decoded_len_)
            clear_fix = false;

        reset_search(ch_pos, clear_fix, false, false);

        memcpy(pys_ + ch_pos, py + ch_pos, py_len - ch_pos);
        pys_[py_len] = '\0';

        while ('\0' != pys_[ch_pos]) {
            if (!add_char(py[ch_pos])) {
                pys_decoded_len_ = ch_pos;
                break;
            }
            ch_pos++;
        }

        // Get spelling ids and starting positions.
        get_spl_start_id();

        // If there are too many spellings, remove the last letter until the spelling
        // number is acceptable.
        while (spl_id_num_ > 9) {
            py_len--;
            reset_search(py_len, false, false, false);
            pys_[py_len] = '\0';
            get_spl_start_id();
        }

        prepare_candidates();

        if (kPrintDebug0) {
            printf("--Matrix Node Pool Used: %d\n", mtrx_nd_pool_used_);
            printf("--DMI Pool Used: %d\n", dmi_pool_used_);

            if (kPrintDebug1) {
                for (PoolPosType pos = 0; pos < dmi_pool_used_; pos++) {
                    debug_print_dmi(pos, 1);
                }
            }
        }

        return ch_pos;
    }

    size_t MatrixSearch::delsearch(size_t pos, bool is_pos_in_splid,
                                   bool clear_fixed_this_step) {
        if (!inited_)
            return 0;

        size_t reset_pos = pos;

        // Out of range for both Pinyin mode and Spelling id mode.
        if (pys_decoded_len_ <= pos) {
            del_in_pys(pos, 1);

            reset_pos = pys_decoded_len_;
            // Decode the string after the un-decoded position
            while ('\0' != pys_[reset_pos]) {
                if (!add_char(pys_[reset_pos])) {
                    pys_decoded_len_ = reset_pos;
                    break;
                }
                reset_pos++;
            }
            get_spl_start_id();
            prepare_candidates();
            return pys_decoded_len_;
        }

        // Spelling id mode, but out of range.
        if (is_pos_in_splid && spl_id_num_ <= pos)
            return pys_decoded_len_;

        // Begin to handle two modes respectively.
        // Pinyin mode by default
        size_t c_py_len = 0;  // The length of composing phrase's Pinyin
        size_t del_py_len = 1;
        if (!is_pos_in_splid) {
            // Pinyin mode is only allowed to delete beyond the fixed lemmas.
            if (fixed_lmas_ > 0 && pos < spl_start_[lma_start_[fixed_lmas_]])
                return pys_decoded_len_;

            del_in_pys(pos, 1);

            // If the deleted character is just the one after the last fixed lemma
            if (pos == spl_start_[lma_start_[fixed_lmas_]]) {
                // If all fixed lemmas have been merged, and the caller of the function
                // request to unlock the last fixed lemma.
                if (kLemmaIdComposing == lma_id_[0] && clear_fixed_this_step) {
                    // Unlock the last sub lemma in the composing phrase. Because it is not
                    // easy to unlock it directly. Instead, we re-decode the modified
                    // composing phrase.
                    c_phrase_.sublma_num--;
                    c_phrase_.length = c_phrase_.sublma_start[c_phrase_.sublma_num];
                    reset_pos = spl_start_[c_phrase_.length];
                    c_py_len = reset_pos;
                }
            }
        } else {
            del_py_len = spl_start_[pos + 1] - spl_start_[pos];

            del_in_pys(spl_start_[pos], del_py_len);

            if (pos >= lma_start_[fixed_lmas_]) {
                c_py_len = 0;
                reset_pos = spl_start_[pos + 1] - del_py_len;
            } else {
                c_py_len = spl_start_[lma_start_[fixed_lmas_]] - del_py_len;
                reset_pos = c_py_len;
                if (c_py_len > 0)
                    merge_fixed_lmas(pos);
            }
        }

        if (c_py_len > 0) {
            assert(c_phrase_.length > 0 && c_py_len ==
                                           c_phrase_.spl_start[c_phrase_.sublma_start[c_phrase_.sublma_num]]);
            // The composing phrase is valid, reset all search space,
            // and begin a new search which will only extend the composing
            // phrase.
            reset_search0();

            dmi_c_phrase_ = true;
            // Extend the composing phrase.
            uint16 c_py_pos = 0;
            while (c_py_pos < c_py_len) {
                bool b_ac_tmp = add_char(pys_[c_py_pos]);
                assert(b_ac_tmp);
                c_py_pos++;
            }
            dmi_c_phrase_ = false;

            // Fixd the composing phrase as the first choice.
            lma_id_num_ = 1;
            fixed_lmas_ = 1;
            fixed_lmas_no1_[0] = 0;  // A composing string is always modified.
            fixed_hzs_ = c_phrase_.length;
            lma_start_[1] = fixed_hzs_;
            lma_id_[0] = kLemmaIdComposing;
            matrix_[spl_start_[fixed_hzs_]].mtrx_nd_fixed = mtrx_nd_pool_ +
                                                            matrix_[spl_start_[fixed_hzs_]].mtrx_nd_pos;
        } else {
            // Reseting search only clear pys_decoded_len_, but the string is kept.
            reset_search(reset_pos, clear_fixed_this_step, false, false);
        }

        // Decode the string after the delete position.
        while ('\0' != pys_[reset_pos]) {
            if (!add_char(pys_[reset_pos])) {
                pys_decoded_len_ = reset_pos;
                break;
            }
            reset_pos++;
        }

        get_spl_start_id();
        prepare_candidates();
        return pys_decoded_len_;
    }

    size_t MatrixSearch::get_candidate_num() {
        if (!inited_ || 0 == pys_decoded_len_ ||
            0 == matrix_[pys_decoded_len_].mtrx_nd_num)
            return 0;

        return 1 + lpi_total_;
    }

    char16 *MatrixSearch::get_candidate(size_t cand_id, char16 *cand_str,
                                        size_t max_len) {
        if (!inited_ || 0 == pys_decoded_len_ || NULL == cand_str)
            return NULL;

        if (0 == cand_id) {
            return get_candidate0(cand_str, max_len, NULL, false);
        } else {
            cand_id--;
        }

        // For this case: the current sentence is a word only, and the user fixed it,
        // so the result will be fixed to the sentence space, and
        // lpi_total_ will be set to 0.
        if (0 == lpi_total_) {
            return get_candidate0(cand_str, max_len, NULL, false);
        }

        LemmaIdType id = lpi_items_[cand_id].id;
        char16 s[kMaxLemmaSize + 1];

        uint16 s_len = lpi_items_[cand_id].lma_len;
        if (s_len > 1) {
            s_len = get_lemma_str(id, s, kMaxLemmaSize + 1);
        } else {
            // For a single character, Hanzi is ready.
            s[0] = lpi_items_[cand_id].hanzi;
            s[1] = static_cast<char16>(0);
        }

        if (s_len > 0 && max_len > s_len) {
            utf16_strncpy(cand_str, s, s_len);
            cand_str[s_len] = (char16) '\0';
            return cand_str;
        }

        return NULL;
    }

    void MatrixSearch::update_dict_freq() {
        if (NULL != user_dict_) {
            // Update the total frequency of all lemmas, including system lemmas and
            // user dictionary lemmas.
            size_t total_freq = user_dict_->get_total_lemma_count();
            dict_trie_->set_total_lemma_count_of_others(total_freq);
        }
    }

    bool MatrixSearch::add_lma_to_userdict(uint16 lma_fr, uint16 lma_to,
                                           float score) {
        if (lma_to - lma_fr <= 1 || NULL == user_dict_)
            return false;

        char16 word_str[kMaxLemmaSize + 1];
        uint16 spl_ids[kMaxLemmaSize];

        uint16 spl_id_fr = 0;

        for (uint16 pos = lma_fr; pos < lma_to; pos++) {
            LemmaIdType lma_id = lma_id_[pos];
            if (is_user_lemma(lma_id)) {
                user_dict_->update_lemma(lma_id, 1, true);
            }
            uint16 lma_len = lma_start_[pos + 1] - lma_start_[pos];
            utf16_strncpy(spl_ids + spl_id_fr, spl_id_ + lma_start_[pos], lma_len);

            uint16 tmp = get_lemma_str(lma_id, word_str + spl_id_fr,
                                       kMaxLemmaSize + 1 - spl_id_fr);
            assert(tmp == lma_len);

            tmp = get_lemma_splids(lma_id, spl_ids + spl_id_fr, lma_len, true);
            if (tmp != lma_len) {
                return false;
            }

            spl_id_fr += lma_len;
        }

        assert(spl_id_fr <= kMaxLemmaSize);

        return user_dict_->put_lemma(static_cast<char16 *>(word_str), spl_ids,
                                     spl_id_fr, 1);
    }

    void MatrixSearch::debug_print_dmi(PoolPosType dmi_pos, uint16 nest_level) {
        if (dmi_pos >= dmi_pool_used_) return;

        DictMatchInfo *dmi = dmi_pool_ + dmi_pos;

        if (1 == nest_level) {
            printf("-----------------%d\'th DMI node begin----------->\n", dmi_pos);
        }
        if (dmi->dict_level > 1) {
            debug_print_dmi(dmi->dmi_fr, nest_level + 1);
        }
        printf("---%d\n", dmi->dict_level);
        printf(" MileStone: %x, %x\n", dmi->dict_handles[0], dmi->dict_handles[1]);
        printf(" Spelling : %s, %d\n", SpellingTrie::get_instance().
                get_spelling_str(dmi->spl_id), dmi->spl_id);
        printf(" Total Pinyin Len: %d\n", dmi->splstr_len);
        if (1 == nest_level) {
            printf("<----------------%d\'th DMI node end--------------\n\n", dmi_pos);
        }
    }

    bool MatrixSearch::try_add_cand0_to_userdict() {
        size_t new_cand_num = get_candidate_num();
        if (fixed_hzs_ > 0 && 1 == new_cand_num) {
            float score_from = 0;
            uint16 lma_id_from = 0;
            uint16 pos = 0;
            bool modified = false;
            while (pos < fixed_lmas_) {
                if (lma_start_[pos + 1] - lma_start_[lma_id_from] >
                    static_cast<uint16>(kMaxLemmaSize)) {
                    float score_to_add =
                            mtrx_nd_pool_[matrix_[spl_start_[lma_start_[pos]]]
                                    .mtrx_nd_pos].score - score_from;
                    if (modified) {
                        score_to_add += 1.0;
                        if (score_to_add > NGram::kMaxScore) {
                            score_to_add = NGram::kMaxScore;
                        }
                        add_lma_to_userdict(lma_id_from, pos, score_to_add);
                    }
                    lma_id_from = pos;
                    score_from += score_to_add;

                    // Clear the flag for next user lemma.
                    modified = false;
                }

                if (0 == fixed_lmas_no1_[pos]) {
                    modified = true;
                }
                pos++;
            }

            // Single-char word is not allowed to add to userdict.
            if (lma_start_[pos] - lma_start_[lma_id_from] > 1) {
                float score_to_add =
                        mtrx_nd_pool_[matrix_[spl_start_[lma_start_[pos]]]
                                .mtrx_nd_pos].score - score_from;
                if (modified) {
                    score_to_add += 1.0;
                    if (score_to_add > NGram::kMaxScore) {
                        score_to_add = NGram::kMaxScore;
                    }
                    add_lma_to_userdict(lma_id_from, pos, score_to_add);
                }
            }
        }
        return true;
    }

// Choose a candidate, and give new candidates for next step.
// If user finishes selection, we will try to communicate with user dictionary
// to add new items or update score of some existing items.
//
// Basic rule:
// 1. If user selects the first choice:
//    1.1. If the first choice is not a sentence, instead, it is a lemma:
//         1.1.1. If the first choice is a user lemma, notify the user
//                dictionary that a user lemma is hit, and add occuring count
//                by 1.
//         1.1.2. If the first choice is a system lemma, do nothing.
//    1.2. If the first choice is a sentence containing more than one lemma:
//         1.2.1. The whole sentence will be added as a user lemma. If the
//                sentence contains user lemmas, -> hit, and add occuring count
//                by 1.
    size_t MatrixSearch::choose(size_t cand_id) {
        if (!inited_ || 0 == pys_decoded_len_)
            return 0;

        if (0 == cand_id) {
            fixed_hzs_ = spl_id_num_;
            matrix_[spl_start_[fixed_hzs_]].mtrx_nd_fixed = mtrx_nd_pool_ +
                                                            matrix_[spl_start_[fixed_hzs_]].mtrx_nd_pos;
            for (size_t pos = fixed_lmas_; pos < lma_id_num_; pos++) {
                fixed_lmas_no1_[pos] = 1;
            }
            fixed_lmas_ = lma_id_num_;
            lpi_total_ = 0;  // Clean all other candidates.

            // 1. It is the first choice
            if (1 == lma_id_num_) {
                // 1.1. The first choice is not a sentence but a lemma
                if (is_user_lemma(lma_id_[0])) {
                    // 1.1.1. The first choice is a user lemma, notify the user dictionary
                    // that it is hit.
                    if (NULL != user_dict_)
                        user_dict_->update_lemma(lma_id_[0], 1, true);
                } else {
                    // 1.1.2. do thing for a system lemma.
                }
            } else {
                // 1.2. The first choice is a sentence.
                // 1.2.1 Try to add the whole sentence to user dictionary, the whole
                // sentence may be splitted into many items.
                if (NULL != user_dict_) {
                    try_add_cand0_to_userdict();
                }
            }
            update_dict_freq();
            return 1;
        } else {
            cand_id--;
        }

        // 2. It is not the full sentence candidate.
        // Find the length of the candidate.
        LemmaIdType id_chosen = lpi_items_[cand_id].id;
        LmaScoreType score_chosen = lpi_items_[cand_id].psb;
        size_t cand_len = lpi_items_[cand_id].lma_len;

        assert(cand_len > 0);

        // Notify the atom dictionary that this item is hit.
        if (is_user_lemma(id_chosen)) {
            if (NULL != user_dict_) {
                user_dict_->update_lemma(id_chosen, 1, true);
            }
            update_dict_freq();
        }

        // 3. Fixed the chosen item.
        // 3.1 Get the steps number.
        size_t step_fr = spl_start_[fixed_hzs_];
        size_t step_to = spl_start_[fixed_hzs_ + cand_len];

        // 3.2 Save the length of the original string.
        size_t pys_decoded_len = pys_decoded_len_;

        // 3.2 Reset the space of the fixed part.
        reset_search(step_to, false, false, true);

        // 3.3 For the last character of the fixed part, the previous DMI
        // information will be kept, while the MTRX information will be re-extended,
        // and only one node will be extended.
        matrix_[step_to].mtrx_nd_num = 0;

        LmaPsbItem lpi_item;
        lpi_item.psb = score_chosen;
        lpi_item.id = id_chosen;

        PoolPosType step_to_dmi_fr = match_dmi(step_to,
                                               spl_id_ + fixed_hzs_, cand_len);
        //用户记忆的词库选择之后有可能会崩溃值为65535，先注释
        //assert(step_to_dmi_fr != static_cast<PoolPosType>(-1));

        extend_mtrx_nd(matrix_[step_fr].mtrx_nd_fixed, &lpi_item, 1,
                       step_to_dmi_fr, step_to);

        matrix_[step_to].mtrx_nd_fixed = mtrx_nd_pool_ + matrix_[step_to].mtrx_nd_pos;
        mtrx_nd_pool_used_ = matrix_[step_to].mtrx_nd_pos +
                             matrix_[step_to].mtrx_nd_num;

        if (id_chosen == lma_id_[fixed_lmas_])
            fixed_lmas_no1_[fixed_lmas_] = 1;
        else
            fixed_lmas_no1_[fixed_lmas_] = 0;
        lma_id_[fixed_lmas_] = id_chosen;
        lma_start_[fixed_lmas_ + 1] = lma_start_[fixed_lmas_] + cand_len;
        fixed_lmas_++;
        fixed_hzs_ = fixed_hzs_ + cand_len;

        while (step_to != pys_decoded_len) {
            bool b = add_char(pys_[step_to]);
            assert(b);
            step_to++;
        }

        if (fixed_hzs_ < spl_id_num_) {
            prepare_candidates();
        } else {
            lpi_total_ = 0;
            if (NULL != user_dict_) {
                try_add_cand0_to_userdict();
            }
        }

        return get_candidate_num();
    }

    size_t MatrixSearch::cancel_last_choice() {
        if (!inited_ || 0 == pys_decoded_len_)
            return 0;

        size_t step_start = 0;
        if (fixed_hzs_ > 0) {
            size_t step_end = spl_start_[fixed_hzs_];
            MatrixNode *end_node = matrix_[step_end].mtrx_nd_fixed;
            assert(NULL != end_node);

            step_start = end_node->from->step;

            if (step_start > 0) {
                DictMatchInfo *dmi = dmi_pool_ + end_node->dmi_fr;
                fixed_hzs_ -= dmi->dict_level;
            } else {
                fixed_hzs_ = 0;
            }

            reset_search(step_start, false, false, false);

            while (pys_[step_start] != '\0') {
                bool b = add_char(pys_[step_start]);
                assert(b);
                step_start++;
            }

            prepare_candidates();
        }
        return get_candidate_num();
    }

    size_t MatrixSearch::get_fixedlen() {
        if (!inited_ || 0 == pys_decoded_len_)
            return 0;
        return fixed_hzs_;
    }

    bool MatrixSearch::prepare_add_char(char ch) {
        if (pys_decoded_len_ >= kMaxRowNum - 1 ||
            (!spl_parser_->is_valid_to_parse(ch) && ch != '\''))
            return false;

        if (dmi_pool_used_ >= kDmiPoolSize) return false;

        pys_[pys_decoded_len_] = ch;
        pys_decoded_len_++;

        MatrixRow *mtrx_this_row = matrix_ + pys_decoded_len_;
        mtrx_this_row->mtrx_nd_pos = mtrx_nd_pool_used_;
        mtrx_this_row->mtrx_nd_num = 0;
        mtrx_this_row->dmi_pos = dmi_pool_used_;
        mtrx_this_row->dmi_num = 0;
        mtrx_this_row->dmi_has_full_id = 0;

        return true;
    }

    bool MatrixSearch::is_split_at(uint16 pos) {
        return !spl_parser_->is_valid_to_parse(pys_[pos - 1]);
    }

    void MatrixSearch::fill_dmi(DictMatchInfo *dmi, MileStoneHandle *handles,
                                PoolPosType dmi_fr, uint16 spl_id,
                                uint16 node_num, unsigned char dict_level,
                                bool splid_end_split, unsigned char splstr_len,
                                unsigned char all_full_id) {
        dmi->dict_handles[0] = handles[0];
        dmi->dict_handles[1] = handles[1];
        dmi->dmi_fr = dmi_fr;
        dmi->spl_id = spl_id;
        dmi->dict_level = dict_level;
        dmi->splid_end_split = splid_end_split ? 1 : 0;
        dmi->splstr_len = splstr_len;
        dmi->all_full_id = all_full_id;
        dmi->c_phrase = 0;
    }

    bool MatrixSearch::add_char(char ch) {
        if (!prepare_add_char(ch))
            return false;
        return add_char_qwerty();
    }

    bool MatrixSearch::add_char_qwerty() {
        matrix_[pys_decoded_len_].mtrx_nd_num = 0;

        bool spl_matched = false;
        uint16 longest_ext = 0;
        // Extend the search matrix, from the oldest unfixed row. ext_len means
        // extending length.
        for (uint16 ext_len = kMaxPinyinSize + 1; ext_len > 0; ext_len--) {
            if (ext_len > pys_decoded_len_ - spl_start_[fixed_hzs_])
                continue;

            // Refer to the declaration of the variable dmi_has_full_id for the
            // explanation of this piece of code. In one word, it is used to prevent
            // from the unwise extending of "shoud ou" but allow the reasonable
            // extending of "heng ao", "lang a", etc.
            if (ext_len > 1 && 0 != longest_ext &&
                0 == matrix_[pys_decoded_len_ - ext_len].dmi_has_full_id) {
                if (xi_an_enabled_)
                    continue;
                else
                    break;
            }

            uint16 oldrow = pys_decoded_len_ - ext_len;

            // 0. If that row is before the last fixed step, ignore.
            if (spl_start_[fixed_hzs_] > oldrow)
                continue;

            // 1. Check if that old row has valid MatrixNode. If no, means that row is
            // not a boundary, either a word boundary or a spelling boundary.
            // If it is for extending composing phrase, it's OK to ignore the 0.
            if (0 == matrix_[oldrow].mtrx_nd_num && !dmi_c_phrase_)
                continue;

            // 2. Get spelling id(s) for the last ext_len chars.
            uint16 spl_idx;
            bool is_pre = false;
            spl_idx = spl_parser_->get_splid_by_str(pys_ + oldrow,
                                                    ext_len, &is_pre);
            if (is_pre)
                spl_matched = true;

            if (0 == spl_idx)
                continue;

            bool splid_end_split = is_split_at(oldrow + ext_len);

            // 3. Extend the DMI nodes of that old row
            // + 1 is to extend an extra node from the root
            for (PoolPosType dmi_pos = matrix_[oldrow].dmi_pos;
                 dmi_pos < matrix_[oldrow].dmi_pos + matrix_[oldrow].dmi_num + 1;
                 dmi_pos++) {
                DictMatchInfo *dmi = dmi_pool_ + dmi_pos;
                if (dmi_pos == matrix_[oldrow].dmi_pos + matrix_[oldrow].dmi_num) {
                    dmi = NULL;  // The last one, NULL means extending from the root.
                } else {
                    // If the dmi is covered by the fixed arrange, ignore it.
                    if (fixed_hzs_ > 0 &&
                        pys_decoded_len_ - ext_len - dmi->splstr_len <
                        spl_start_[fixed_hzs_]) {
                        continue;
                    }
                    // If it is not in mode for composing phrase, and the source DMI node
                    // is marked for composing phrase, ignore this node.
                    if (dmi->c_phrase != 0 && !dmi_c_phrase_) {
                        continue;
                    }
                }

                // For example, if "gao" is extended, "g ao" is not allowed.
                // or "zh" has been passed, "z h" is not allowed.
                // Both word and word-connection will be prevented.
                if (longest_ext > ext_len) {
                    if (NULL == dmi && 0 == matrix_[oldrow].dmi_has_full_id) {
                        continue;
                    }

                    // "z h" is not allowed.
                    if (NULL != dmi && spl_trie_->is_half_id(dmi->spl_id)) {
                        continue;
                    }
                }

                dep_->splids_extended = 0;
                if (NULL != dmi) {
                    uint16 prev_ids_num = dmi->dict_level;
                    if ((!dmi_c_phrase_ && prev_ids_num >= kMaxLemmaSize) ||
                        (dmi_c_phrase_ && prev_ids_num >= kMaxRowNum)) {
                        continue;
                    }

                    DictMatchInfo *d = dmi;
                    while (d) {
                        dep_->splids[--prev_ids_num] = d->spl_id;
                        if ((PoolPosType) -1 == d->dmi_fr)
                            break;
                        d = dmi_pool_ + d->dmi_fr;
                    }
                    assert(0 == prev_ids_num);
                    dep_->splids_extended = dmi->dict_level;
                }
                dep_->splids[dep_->splids_extended] = spl_idx;
                dep_->ext_len = ext_len;
                dep_->splid_end_split = splid_end_split;

                dep_->id_num = 1;
                dep_->id_start = spl_idx;
                if (spl_trie_->is_half_id(spl_idx)) {
                    // Get the full id list
                    dep_->id_num = spl_trie_->half_to_full(spl_idx, &(dep_->id_start));
                    assert(dep_->id_num > 0);
                }

                uint16 new_dmi_num;

                new_dmi_num = extend_dmi(dep_, dmi);

                if (new_dmi_num > 0) {
                    if (dmi_c_phrase_) {
                        dmi_pool_[dmi_pool_used_].c_phrase = 1;
                    }
                    matrix_[pys_decoded_len_].dmi_num += new_dmi_num;
                    dmi_pool_used_ += new_dmi_num;

                    if (!spl_trie_->is_half_id(spl_idx))
                        matrix_[pys_decoded_len_].dmi_has_full_id = 1;
                }

                // If get candiate lemmas, try to extend the path
                if (lpi_total_ > 0) {
                    uint16 fr_row;
                    if (NULL == dmi) {
                        fr_row = oldrow;
                    } else {
                        assert(oldrow >= dmi->splstr_len);
                        fr_row = oldrow - dmi->splstr_len;
                    }
                    for (PoolPosType mtrx_nd_pos = matrix_[fr_row].mtrx_nd_pos;
                         mtrx_nd_pos < matrix_[fr_row].mtrx_nd_pos +
                                       matrix_[fr_row].mtrx_nd_num;
                         mtrx_nd_pos++) {
                        MatrixNode *mtrx_nd = mtrx_nd_pool_ + mtrx_nd_pos;

                        extend_mtrx_nd(mtrx_nd, lpi_items_, lpi_total_,
                                       dmi_pool_used_ - new_dmi_num, pys_decoded_len_);
                        if (longest_ext == 0)
                            longest_ext = ext_len;
                    }
                }
            }  // for dmi_pos
        }  // for ext_len
        mtrx_nd_pool_used_ += matrix_[pys_decoded_len_].mtrx_nd_num;

        if (dmi_c_phrase_)
            return true;

        return (matrix_[pys_decoded_len_].mtrx_nd_num != 0 || spl_matched);
    }

    void MatrixSearch::prepare_candidates() {
        // Get candiates from the first un-fixed step.
        uint16 lma_size_max = kMaxLemmaSize;
        if (lma_size_max > spl_id_num_ - fixed_hzs_)
            lma_size_max = spl_id_num_ - fixed_hzs_;

        uint16 lma_size = lma_size_max;

        // If the full sentense candidate's unfixed part may be the same with a normal
        // lemma. Remove the lemma candidate in this case.
        char16 fullsent[kMaxLemmaSize + 1];
        char16 *pfullsent = NULL;
        uint16 sent_len;
        pfullsent = get_candidate0(fullsent, kMaxLemmaSize + 1, &sent_len, true);

        // If the unfixed part contains more than one ids, it is not necessary to
        // check whether a lemma's string is the same to the unfixed part of the full
        // sentence candidate, so, set it to NULL;
        if (sent_len > kMaxLemmaSize)
            pfullsent = NULL;

        lpi_total_ = 0;
        size_t lpi_num_full_match = 0;  // Number of items which are fully-matched.
        while (lma_size > 0) {
            size_t lma_num;
            lma_num = get_lpis(spl_id_ + fixed_hzs_, lma_size,
                               lpi_items_ + lpi_total_,
                               size_t(kMaxLmaPsbItems - lpi_total_),
                               pfullsent, lma_size == lma_size_max);

            if (lma_num > 0) {
                lpi_total_ += lma_num;
                // For next lemma candidates which are not the longest, it is not
                // necessary to compare with the full sentence candiate.
                pfullsent = NULL;
            }
            if (lma_size == lma_size_max) {
                lpi_num_full_match = lpi_total_;
            }
            lma_size--;
        }

        // Sort those partially-matched items by their unified scores.
        myqsort(lpi_items_ + lpi_num_full_match, lpi_total_ - lpi_num_full_match,
                sizeof(LmaPsbItem), cmp_lpi_with_unified_psb);

        if (kPrintDebug0) {
            printf("-----Prepare candidates, score:\n");
            for (size_t a = 0; a < lpi_total_; a++) {
                printf("[%03d]%d    ", a, lpi_items_[a].psb);
                if ((a + 1) % 6 == 0) printf("\n");
            }
            printf("\n");
        }

        if (kPrintDebug0) {
            printf("--- lpi_total_ = %d\n", lpi_total_);
        }
    }

    const char *MatrixSearch::get_pystr(size_t *decoded_len) {
        if (!inited_ || NULL == decoded_len)
            return NULL;

        *decoded_len = pys_decoded_len_;
        return pys_;
    }

    void MatrixSearch::merge_fixed_lmas(size_t del_spl_pos) {
        if (fixed_lmas_ == 0)
            return;
        // Update spelling segmentation information first.
        spl_id_num_ -= 1;
        uint16 del_py_len = spl_start_[del_spl_pos + 1] - spl_start_[del_spl_pos];
        for (size_t pos = del_spl_pos; pos <= spl_id_num_; pos++) {
            spl_start_[pos] = spl_start_[pos + 1] - del_py_len;
            if (pos == spl_id_num_)
                break;
            spl_id_[pos] = spl_id_[pos + 1];
        }

        // Begin to merge.
        uint16 phrase_len = 0;

        // Update the spelling ids to the composing phrase.
        // We need to convert these ids into full id in the future.
        memcpy(c_phrase_.spl_ids, spl_id_, spl_id_num_ * sizeof(uint16));
        memcpy(c_phrase_.spl_start, spl_start_, (spl_id_num_ + 1) * sizeof(uint16));

        // If composing phrase has not been created, first merge all fixed
        //  lemmas into a composing phrase without deletion.
        if (fixed_lmas_ > 1 || kLemmaIdComposing != lma_id_[0]) {
            uint16 bp = 1;  // Begin position of real fixed lemmas.
            // There is no existing composing phrase.
            if (kLemmaIdComposing != lma_id_[0]) {
                c_phrase_.sublma_num = 0;
                bp = 0;
            }

            uint16 sub_num = c_phrase_.sublma_num;
            for (uint16 pos = bp; pos <= fixed_lmas_; pos++) {
                c_phrase_.sublma_start[sub_num + pos - bp] = lma_start_[pos];
                if (lma_start_[pos] > del_spl_pos) {
                    c_phrase_.sublma_start[sub_num + pos - bp] -= 1;
                }

                if (pos == fixed_lmas_)
                    break;

                uint16 lma_len;
                char16 *lma_str = c_phrase_.chn_str +
                                  c_phrase_.sublma_start[sub_num] + phrase_len;

                lma_len = get_lemma_str(lma_id_[pos], lma_str, kMaxRowNum - phrase_len);
                assert(lma_len == lma_start_[pos + 1] - lma_start_[pos]);
                phrase_len += lma_len;
            }
            assert(phrase_len == lma_start_[fixed_lmas_]);
            c_phrase_.length = phrase_len;  // will be deleted by 1
            c_phrase_.sublma_num += fixed_lmas_ - bp;
        } else {
            for (uint16 pos = 0; pos <= c_phrase_.sublma_num; pos++) {
                if (c_phrase_.sublma_start[pos] > del_spl_pos) {
                    c_phrase_.sublma_start[pos] -= 1;
                }
            }
            phrase_len = c_phrase_.length;
        }

        assert(phrase_len > 0);
        if (1 == phrase_len) {
            // After the only one is deleted, nothing will be left.
            fixed_lmas_ = 0;
            return;
        }

        // Delete the Chinese character in the merged phrase.
        // The corresponding elements in spl_ids and spl_start of the
        // phrase have been deleted.
        char16 *chn_str = c_phrase_.chn_str + del_spl_pos;
        for (uint16 pos = 0;
             pos < c_phrase_.sublma_start[c_phrase_.sublma_num] - del_spl_pos;
             pos++) {
            chn_str[pos] = chn_str[pos + 1];
        }
        c_phrase_.length -= 1;

        // If the deleted spelling id is in a sub lemma which contains more than
        // one id, del_a_sub will be false; but if the deleted id is in a sub lemma
        // which only contains 1 id, the whole sub lemma needs to be deleted, so
        // del_a_sub will be true.
        bool del_a_sub = false;
        for (uint16 pos = 1; pos <= c_phrase_.sublma_num; pos++) {
            if (c_phrase_.sublma_start[pos - 1] ==
                c_phrase_.sublma_start[pos]) {
                del_a_sub = true;
            }
            if (del_a_sub) {
                c_phrase_.sublma_start[pos - 1] =
                        c_phrase_.sublma_start[pos];
            }
        }
        if (del_a_sub)
            c_phrase_.sublma_num -= 1;

        return;
    }

    void MatrixSearch::get_spl_start_id() {
        lma_id_num_ = 0;
        lma_start_[0] = 0;

        spl_id_num_ = 0;
        spl_start_[0] = 0;
        if (!inited_ || 0 == pys_decoded_len_ ||
            0 == matrix_[pys_decoded_len_].mtrx_nd_num)
            return;

        // Calculate number of lemmas and spellings
        // Only scan those part which is not fixed.
        lma_id_num_ = fixed_lmas_;
        spl_id_num_ = fixed_hzs_;

        MatrixNode *mtrx_nd = mtrx_nd_pool_ + matrix_[pys_decoded_len_].mtrx_nd_pos;
        while (mtrx_nd != mtrx_nd_pool_) {
            if (fixed_hzs_ > 0) {
                if (mtrx_nd->step <= spl_start_[fixed_hzs_])
                    break;
            }

            // Update the spelling segamentation information
            unsigned char word_splstr_len = 0;
            PoolPosType dmi_fr = mtrx_nd->dmi_fr;
            if ((PoolPosType) -1 != dmi_fr)
                word_splstr_len = dmi_pool_[dmi_fr].splstr_len;

            while ((PoolPosType) -1 != dmi_fr) {
                spl_start_[spl_id_num_ + 1] = mtrx_nd->step -
                                              (word_splstr_len - dmi_pool_[dmi_fr].splstr_len);
                spl_id_[spl_id_num_] = dmi_pool_[dmi_fr].spl_id;
                spl_id_num_++;
                dmi_fr = dmi_pool_[dmi_fr].dmi_fr;
            }

            // Update the lemma segmentation information
            lma_start_[lma_id_num_ + 1] = spl_id_num_;
            lma_id_[lma_id_num_] = mtrx_nd->id;
            lma_id_num_++;

            mtrx_nd = mtrx_nd->from;
        }

        // Reverse the result of spelling info
        for (size_t pos = fixed_hzs_;
             pos < fixed_hzs_ + (spl_id_num_ - fixed_hzs_ + 1) / 2; pos++) {
            if (spl_id_num_ + fixed_hzs_ - pos != pos + 1) {
                spl_start_[pos + 1] ^= spl_start_[spl_id_num_ - pos + fixed_hzs_];
                spl_start_[spl_id_num_ - pos + fixed_hzs_] ^= spl_start_[pos + 1];
                spl_start_[pos + 1] ^= spl_start_[spl_id_num_ - pos + fixed_hzs_];

                spl_id_[pos] ^= spl_id_[spl_id_num_ + fixed_hzs_ - pos - 1];
                spl_id_[spl_id_num_ + fixed_hzs_ - pos - 1] ^= spl_id_[pos];
                spl_id_[pos] ^= spl_id_[spl_id_num_ + fixed_hzs_ - pos - 1];
            }
        }

        // Reverse the result of lemma info
        for (size_t pos = fixed_lmas_;
             pos < fixed_lmas_ + (lma_id_num_ - fixed_lmas_ + 1) / 2; pos++) {
            assert(lma_id_num_ + fixed_lmas_ - pos - 1 >= pos);

            if (lma_id_num_ + fixed_lmas_ - pos > pos + 1) {
                lma_start_[pos + 1] ^= lma_start_[lma_id_num_ - pos + fixed_lmas_];
                lma_start_[lma_id_num_ - pos + fixed_lmas_] ^= lma_start_[pos + 1];
                lma_start_[pos + 1] ^= lma_start_[lma_id_num_ - pos + fixed_lmas_];

                lma_id_[pos] ^= lma_id_[lma_id_num_ - 1 - pos + fixed_lmas_];
                lma_id_[lma_id_num_ - 1 - pos + fixed_lmas_] ^= lma_id_[pos];
                lma_id_[pos] ^= lma_id_[lma_id_num_ - 1 - pos + fixed_lmas_];
            }
        }

        for (size_t pos = fixed_lmas_ + 1; pos <= lma_id_num_; pos++) {
            if (pos < lma_id_num_)
                lma_start_[pos] = lma_start_[pos - 1] +
                                  (lma_start_[pos] - lma_start_[pos + 1]);
            else
                lma_start_[pos] = lma_start_[pos - 1] + lma_start_[pos] -
                                  lma_start_[fixed_lmas_];
        }

        // Find the last fixed position
        fixed_hzs_ = 0;
        for (size_t pos = spl_id_num_; pos > 0; pos--) {
            if (NULL != matrix_[spl_start_[pos]].mtrx_nd_fixed) {
                fixed_hzs_ = pos;
                break;
            }
        }

        return;
    }

    size_t MatrixSearch::get_spl_start(const uint16 *&spl_start) {
        get_spl_start_id();
        spl_start = spl_start_;
        return spl_id_num_;
    }

    size_t MatrixSearch::extend_dmi(DictExtPara *dep, DictMatchInfo *dmi_s) {
        if (dmi_pool_used_ >= kDmiPoolSize) return 0;

        if (dmi_c_phrase_)
            return extend_dmi_c(dep, dmi_s);

        LpiCache &lpi_cache = LpiCache::get_instance();
        uint16 splid = dep->splids[dep->splids_extended];

        bool cached = false;
        if (0 == dep->splids_extended)
            cached = lpi_cache.is_cached(splid);

        // 1. If this is a half Id, get its corresponding full starting Id and
        // number of full Id.
        size_t ret_val = 0;
        PoolPosType mtrx_dmi_fr = (PoolPosType) -1;  // From which dmi node

        lpi_total_ = 0;

        MileStoneHandle from_h[3];
        from_h[0] = 0;
        from_h[1] = 0;

        if (0 != dep->splids_extended) {
            from_h[0] = dmi_s->dict_handles[0];
            from_h[1] = dmi_s->dict_handles[1];
        }

        // 2. Begin exgtending in the system dictionary
        size_t lpi_num = 0;
        MileStoneHandle handles[2];
        handles[0] = handles[1] = 0;
        if (from_h[0] > 0 || NULL == dmi_s) {
            handles[0] = dict_trie_->extend_dict(from_h[0], dep, lpi_items_,
                                                 kMaxLmaPsbItems, &lpi_num);
        }
        if (handles[0] > 0)
            lpi_total_ = lpi_num;

        if (NULL == dmi_s) {  // from root
            assert(0 != handles[0]);
            mtrx_dmi_fr = dmi_pool_used_;
        }

        // 3. Begin extending in the user dictionary
        if (NULL != user_dict_ && (from_h[1] > 0 || NULL == dmi_s)) {
            handles[1] = user_dict_->extend_dict(from_h[1], dep,
                                                 lpi_items_ + lpi_total_,
                                                 kMaxLmaPsbItems - lpi_total_,
                                                 &lpi_num);
            if (handles[1] > 0) {
                if (kPrintDebug0) {
                    for (size_t t = 0; t < lpi_num; t++) {
                        printf("--Extend in user dict: uid:%d uscore:%d\n",
                               lpi_items_[lpi_total_ + t].id,
                               lpi_items_[lpi_total_ + t].psb);
                    }
                }
                lpi_total_ += lpi_num;
            }
        }

        if (0 != handles[0] || 0 != handles[1]) {
            if (dmi_pool_used_ >= kDmiPoolSize) return 0;

            DictMatchInfo *dmi_add = dmi_pool_ + dmi_pool_used_;
            if (NULL == dmi_s) {
                fill_dmi(dmi_add, handles,
                         (PoolPosType) -1, splid,
                         1, 1, dep->splid_end_split, dep->ext_len,
                         spl_trie_->is_half_id(splid) ? 0 : 1);
            } else {
                fill_dmi(dmi_add, handles,
                         dmi_s - dmi_pool_, splid, 1,
                         dmi_s->dict_level + 1, dep->splid_end_split,
                         dmi_s->splstr_len + dep->ext_len,
                         spl_trie_->is_half_id(splid) ? 0 : dmi_s->all_full_id);
            }

            ret_val = 1;
        }

        if (!cached) {
            if (0 == lpi_total_)
                return ret_val;

            if (kPrintDebug0) {
                printf("--- lpi_total_ = %d\n", lpi_total_);
            }

            myqsort(lpi_items_, lpi_total_, sizeof(LmaPsbItem), cmp_lpi_with_psb);
            if (NULL == dmi_s && spl_trie_->is_half_id(splid))
                lpi_total_ = lpi_cache.put_cache(splid, lpi_items_, lpi_total_);
        } else {
            assert(spl_trie_->is_half_id(splid));
            lpi_total_ = lpi_cache.get_cache(splid, lpi_items_, kMaxLmaPsbItems);
        }

        return ret_val;
    }

    size_t MatrixSearch::extend_dmi_c(DictExtPara *dep, DictMatchInfo *dmi_s) {
        lpi_total_ = 0;

        uint16 pos = dep->splids_extended;
        assert(dmi_c_phrase_);
        if (pos >= c_phrase_.length)
            return 0;

        uint16 splid = dep->splids[pos];
        if (splid == c_phrase_.spl_ids[pos]) {
            DictMatchInfo *dmi_add = dmi_pool_ + dmi_pool_used_;
            MileStoneHandle handles[2];  // Actually never used.
            if (NULL == dmi_s)
                fill_dmi(dmi_add, handles,
                         (PoolPosType) -1, splid,
                         1, 1, dep->splid_end_split, dep->ext_len,
                         spl_trie_->is_half_id(splid) ? 0 : 1);
            else
                fill_dmi(dmi_add, handles,
                         dmi_s - dmi_pool_, splid, 1,
                         dmi_s->dict_level + 1, dep->splid_end_split,
                         dmi_s->splstr_len + dep->ext_len,
                         spl_trie_->is_half_id(splid) ? 0 : dmi_s->all_full_id);

            if (pos == c_phrase_.length - 1) {
                lpi_items_[0].id = kLemmaIdComposing;
                lpi_items_[0].psb = 0;  // 0 is bigger than normal lemma score.
                lpi_total_ = 1;
            }
            return 1;
        }
        return 0;
    }

    size_t MatrixSearch::extend_mtrx_nd(MatrixNode *mtrx_nd, LmaPsbItem lpi_items[],
                                        size_t lpi_num, PoolPosType dmi_fr,
                                        size_t res_row) {
        assert(NULL != mtrx_nd);
        matrix_[res_row].mtrx_nd_fixed = NULL;

        if (mtrx_nd_pool_used_ >= kMtrxNdPoolSize - kMaxNodeARow)
            return 0;

        if (0 == mtrx_nd->step) {
            // Because the list is sorted, if the source step is 0, it is only
            // necessary to pick up the first kMaxNodeARow items.
            if (lpi_num > kMaxNodeARow)
                lpi_num = kMaxNodeARow;
        }

        MatrixNode *mtrx_nd_res_min = mtrx_nd_pool_ + matrix_[res_row].mtrx_nd_pos;
        for (size_t pos = 0; pos < lpi_num; pos++) {
            float score = mtrx_nd->score + lpi_items[pos].psb;
            if (pos > 0 && score - PRUMING_SCORE > mtrx_nd_res_min->score)
                break;

            // Try to add a new node
            size_t mtrx_nd_num = matrix_[res_row].mtrx_nd_num;
            MatrixNode *mtrx_nd_res = mtrx_nd_res_min + mtrx_nd_num;
            bool replace = false;
            // Find its position
            while (mtrx_nd_res > mtrx_nd_res_min && score < (mtrx_nd_res - 1)->score) {
                if (static_cast<size_t>(mtrx_nd_res - mtrx_nd_res_min) < kMaxNodeARow)
                    *mtrx_nd_res = *(mtrx_nd_res - 1);
                mtrx_nd_res--;
                replace = true;
            }
            if (replace || (mtrx_nd_num < kMaxNodeARow &&
                            matrix_[res_row].mtrx_nd_pos + mtrx_nd_num < kMtrxNdPoolSize)) {
                mtrx_nd_res->id = lpi_items[pos].id;
                mtrx_nd_res->score = score;
                mtrx_nd_res->from = mtrx_nd;
                mtrx_nd_res->dmi_fr = dmi_fr;
                mtrx_nd_res->step = res_row;
                if (matrix_[res_row].mtrx_nd_num < kMaxNodeARow)
                    matrix_[res_row].mtrx_nd_num++;
            }
        }
        return matrix_[res_row].mtrx_nd_num;
    }

    PoolPosType MatrixSearch::match_dmi(size_t step_to, uint16 spl_ids[],
                                        uint16 spl_id_num) {
        if (pys_decoded_len_ < step_to || 0 == matrix_[step_to].dmi_num) {
            return static_cast<PoolPosType>(-1);
        }

        for (PoolPosType dmi_pos = 0; dmi_pos < matrix_[step_to].dmi_num; dmi_pos++) {
            DictMatchInfo *dmi = dmi_pool_ + matrix_[step_to].dmi_pos + dmi_pos;

            if (dmi->dict_level != spl_id_num)
                continue;

            bool matched = true;
            for (uint16 spl_pos = 0; spl_pos < spl_id_num; spl_pos++) {
                if (spl_ids[spl_id_num - spl_pos - 1] != dmi->spl_id) {
                    matched = false;
                    break;
                }

                dmi = dmi_pool_ + dmi->dmi_fr;
            }
            if (matched) {
                return matrix_[step_to].dmi_pos + dmi_pos;
            }
        }

        return static_cast<PoolPosType>(-1);
    }

    char16 *MatrixSearch::get_candidate0(char16 *cand_str, size_t max_len,
                                         uint16 *retstr_len,
                                         bool only_unfixed) {
        if (pys_decoded_len_ == 0 ||
            matrix_[pys_decoded_len_].mtrx_nd_num == 0)
            return NULL;

        LemmaIdType idxs[kMaxRowNum];
        size_t id_num = 0;

        MatrixNode *mtrx_nd = mtrx_nd_pool_ + matrix_[pys_decoded_len_].mtrx_nd_pos;

        if (kPrintDebug0) {
            printf("--- sentence score: %f\n", mtrx_nd->score);
        }

        if (kPrintDebug1) {
            printf("==============Sentence DMI (reverse order) begin===========>>\n");
        }

        while (mtrx_nd != NULL) {
            idxs[id_num] = mtrx_nd->id;
            id_num++;

            if (kPrintDebug1) {
                printf("---MatrixNode [step: %d, lma_idx: %d, total score:%.5f]\n",
                       mtrx_nd->step, mtrx_nd->id, mtrx_nd->score);
                debug_print_dmi(mtrx_nd->dmi_fr, 1);
            }

            mtrx_nd = mtrx_nd->from;
        }

        if (kPrintDebug1) {
            printf("<<==============Sentence DMI (reverse order) end=============\n");
        }

        size_t ret_pos = 0;
        do {
            id_num--;
            if (0 == idxs[id_num])
                continue;

            char16 str[kMaxLemmaSize + 1];
            uint16 str_len = get_lemma_str(idxs[id_num], str, kMaxLemmaSize + 1);
            if (str_len > 0 && ((!only_unfixed && max_len - ret_pos > str_len) ||
                                (only_unfixed && max_len - ret_pos + fixed_hzs_ > str_len))) {
                if (!only_unfixed)
                    utf16_strncpy(cand_str + ret_pos, str, str_len);
                else if (ret_pos >= fixed_hzs_)
                    utf16_strncpy(cand_str + ret_pos - fixed_hzs_, str, str_len);

                ret_pos += str_len;
            } else {
                return NULL;
            }
        } while (id_num != 0);

        if (!only_unfixed) {
            if (NULL != retstr_len)
                *retstr_len = ret_pos;
            cand_str[ret_pos] = (char16) '\0';
        } else {
            if (NULL != retstr_len)
                *retstr_len = ret_pos - fixed_hzs_;
            cand_str[ret_pos - fixed_hzs_] = (char16) '\0';
        }
        return cand_str;
    }

    size_t MatrixSearch::get_lpis(const uint16 *splid_str, size_t splid_str_len,
                                  LmaPsbItem *lma_buf, size_t max_lma_buf,
                                  const char16 *pfullsent, bool sort_by_psb) {
        if (splid_str_len > kMaxLemmaSize)
            return 0;

        size_t num1 = dict_trie_->get_lpis(splid_str, splid_str_len,
                                           lma_buf, max_lma_buf);
        size_t num2 = 0;
        if (NULL != user_dict_) {
            num2 = user_dict_->get_lpis(splid_str, splid_str_len,
                                        lma_buf + num1, max_lma_buf - num1);
        }

        size_t num = num1 + num2;

        if (0 == num)
            return 0;

        // Remove repeated items.
        if (splid_str_len > 1) {
            LmaPsbStrItem *lpsis = reinterpret_cast<LmaPsbStrItem *>(lma_buf + num);
            size_t lpsi_num = (max_lma_buf - num) * sizeof(LmaPsbItem) /
                              sizeof(LmaPsbStrItem);
            assert(lpsi_num > num);
            if (num > lpsi_num) num = lpsi_num;
            lpsi_num = num;

            for (size_t pos = 0; pos < lpsi_num; pos++) {
                lpsis[pos].lpi = lma_buf[pos];
                get_lemma_str(lma_buf[pos].id, lpsis[pos].str, kMaxLemmaSize + 1);
            }

            myqsort(lpsis, lpsi_num, sizeof(LmaPsbStrItem), cmp_lpsi_with_str);

            size_t remain_num = 0;
            for (size_t pos = 0; pos < lpsi_num; pos++) {
                if (pos > 0 && utf16_strcmp(lpsis[pos].str, lpsis[pos - 1].str) == 0) {
                    if (lpsis[pos].lpi.psb < lpsis[pos - 1].lpi.psb) {
                        assert(remain_num > 0);
                        lma_buf[remain_num - 1] = lpsis[pos].lpi;
                    }
                    continue;
                }
                if (NULL != pfullsent && utf16_strcmp(lpsis[pos].str, pfullsent) == 0)
                    continue;

                lma_buf[remain_num] = lpsis[pos].lpi;
                remain_num++;
            }

            // Update the result number
            num = remain_num;
        } else {
            // For single character, some characters have more than one spelling, for
            // example, "de" and "di" are all valid for a Chinese character, so when
            // the user input  "d", repeated items are generated.
            // For single character lemmas, Hanzis will be gotten
            for (size_t pos = 0; pos < num; pos++) {
                char16 hanzis[2];
                get_lemma_str(lma_buf[pos].id, hanzis, 2);
                lma_buf[pos].hanzi = hanzis[0];
            }

            myqsort(lma_buf, num, sizeof(LmaPsbItem), cmp_lpi_with_hanzi);

            size_t remain_num = 0;
            for (size_t pos = 0; pos < num; pos++) {
                if (pos > 0 && lma_buf[pos].hanzi == lma_buf[pos - 1].hanzi) {
                    if (NULL != pfullsent &&
                        static_cast<char16>(0) == pfullsent[1] &&
                        lma_buf[pos].hanzi == pfullsent[0])
                        continue;

                    if (lma_buf[pos].psb < lma_buf[pos - 1].psb) {
                        assert(remain_num > 0);
                        assert(lma_buf[remain_num - 1].hanzi == lma_buf[pos].hanzi);
                        lma_buf[remain_num - 1] = lma_buf[pos];
                    }
                    continue;
                }
                if (NULL != pfullsent &&
                    static_cast<char16>(0) == pfullsent[1] &&
                    lma_buf[pos].hanzi == pfullsent[0])
                    continue;

                lma_buf[remain_num] = lma_buf[pos];
                remain_num++;
            }

            num = remain_num;
        }

        if (sort_by_psb) {
            myqsort(lma_buf, num, sizeof(LmaPsbItem), cmp_lpi_with_psb);
        }
        return num;
    }

    uint16 MatrixSearch::get_lemma_str(LemmaIdType id_lemma, char16 *str_buf,
                                       uint16 str_max) {
        uint16 str_len = 0;

        if (is_system_lemma(id_lemma)) {
            str_len = dict_trie_->get_lemma_str(id_lemma, str_buf, str_max);
        } else if (is_user_lemma(id_lemma)) {
            if (NULL != user_dict_) {
                str_len = user_dict_->get_lemma_str(id_lemma, str_buf, str_max);
            } else {
                str_len = 0;
                str_buf[0] = static_cast<char16>('\0');
            }
        } else if (is_composing_lemma(id_lemma)) {
            if (str_max <= 1)
                return 0;
            str_len = c_phrase_.sublma_start[c_phrase_.sublma_num];
            if (str_len > str_max - 1)
                str_len = str_max - 1;
            utf16_strncpy(str_buf, c_phrase_.chn_str, str_len);
            str_buf[str_len] = (char16) '\0';
            return str_len;
        }

        return str_len;
    }

    uint16 MatrixSearch::get_lemma_splids(LemmaIdType id_lemma, uint16 *splids,
                                          uint16 splids_max, bool arg_valid) {
        uint16 splid_num = 0;

        if (arg_valid) {
            for (splid_num = 0; splid_num < splids_max; splid_num++) {
                if (spl_trie_->is_half_id(splids[splid_num]))
                    break;
            }
            if (splid_num == splids_max)
                return splid_num;
        }

        if (is_system_lemma(id_lemma)) {
            splid_num = dict_trie_->get_lemma_splids(id_lemma, splids, splids_max,
                                                     arg_valid);
        } else if (is_user_lemma(id_lemma)) {
            if (NULL != user_dict_) {
                splid_num = user_dict_->get_lemma_splids(id_lemma, splids, splids_max,
                                                         arg_valid);
            } else {
                splid_num = 0;
            }
        } else if (is_composing_lemma(id_lemma)) {
            if (c_phrase_.length > splids_max) {
                return 0;
            }
            for (uint16 pos = 0; pos < c_phrase_.length; pos++) {
                splids[pos] = c_phrase_.spl_ids[pos];
                if (spl_trie_->is_half_id(splids[pos])) {
                    return 0;
                }
            }
        }
        return splid_num;
    }

    size_t MatrixSearch::inner_predict(const char16 *fixed_buf, uint16 fixed_len,
                                       char16 predict_buf[][kMaxPredictSize + 1],
                                       size_t buf_len) {
        size_t res_total = 0;
        memset(npre_items_, 0, sizeof(NPredictItem) * npre_items_len_);
        // In order to shorten the comments, j-character candidates predicted by
        // i-character prefix are called P(i,j). All candiates predicted by
        // i-character prefix are called P(i,*)
        // Step 1. Get P(kMaxPredictSize, *) and sort them, here
        // P(kMaxPredictSize, *) == P(kMaxPredictSize, 1)
        for (size_t len = fixed_len; len > 0; len--) {
            // How many blank items are available
            size_t this_max = npre_items_len_ - res_total;
            size_t res_this;
            // If the history is longer than 1, and we can not get prediction from
            // lemmas longer than 2, in this case, we will add lemmas with
            // highest scores as the prediction result.
            if (fixed_len > 1 && 1 == len && 0 == res_total) {
                // Try to find if recent n (n>1) characters can be a valid lemma in system
                // dictionary.
                bool nearest_n_word = false;
                for (size_t nlen = 2; nlen <= fixed_len; nlen++) {
                    if (dict_trie_->get_lemma_id(fixed_buf + fixed_len - nlen, nlen) > 0) {
                        nearest_n_word = true;
                        break;
                    }
                }
                res_this = dict_trie_->predict_top_lmas(nearest_n_word ? len : 0,
                                                        npre_items_ + res_total,
                                                        this_max, res_total);
                res_total += res_this;
            }

            // How many blank items are available
            this_max = npre_items_len_ - res_total;
            res_this = 0;
            if (!kOnlyUserDictPredict) {
                res_this =
                        dict_trie_->predict(fixed_buf + fixed_len - len, len,
                                            npre_items_ + res_total, this_max,
                                            res_total);
            }

            if (NULL != user_dict_) {
                res_this = res_this +
                           user_dict_->predict(fixed_buf + fixed_len - len, len,
                                               npre_items_ + res_total + res_this,
                                               this_max - res_this, res_total + res_this);
            }

            if (kPredictLimitGt1) {
                myqsort(npre_items_ + res_total, res_this, sizeof(NPredictItem),
                        cmp_npre_by_score);

                if (len > 3) {
                    if (res_this > kMaxPredictNumByGt3)
                        res_this = kMaxPredictNumByGt3;
                } else if (3 == len) {
                    if (res_this > kMaxPredictNumBy3)
                        res_this = kMaxPredictNumBy3;
                } else if (2 == len) {
                    if (res_this > kMaxPredictNumBy2)
                        res_this = kMaxPredictNumBy2;
                }
            }

            res_total += res_this;
        }

        res_total = remove_duplicate_npre(npre_items_, res_total);

        if (kPreferLongHistoryPredict) {
            myqsort(npre_items_, res_total, sizeof(NPredictItem),
                    cmp_npre_by_hislen_score);
        } else {
            myqsort(npre_items_, res_total, sizeof(NPredictItem),
                    cmp_npre_by_score);
        }

        if (buf_len < res_total) {
            res_total = buf_len;
        }

        if (kPrintDebug2) {
            printf("/////////////////Predicted Items Begin////////////////////>>\n");
            for (size_t i = 0; i < res_total; i++) {
                printf("---");
                for (size_t j = 0; j < kMaxPredictSize; j++) {
                    printf("%d  ", npre_items_[i].pre_hzs[j]);
                }
                printf("\n");
            }
            printf("<<///////////////Predicted Items End////////////////////////\n");
        }

        for (size_t i = 0; i < res_total; i++) {
            utf16_strncpy(predict_buf[i], npre_items_[i].pre_hzs,
                          kMaxPredictSize);
            predict_buf[i][kMaxPredictSize] = '\0';
        }

        return res_total;
    }

    size_t MatrixSearch::get_predicts(const char16 fixed_buf[],
                                      char16 predict_buf[][kMaxPredictSize + 1],
                                      size_t buf_len) {
        size_t fixed_len = utf16_strlen(fixed_buf);
        if (0 == fixed_len || fixed_len > kMaxPredictSize || 0 == buf_len)
            return 0;

        return inner_predict(fixed_buf, fixed_len, predict_buf, buf_len);
    }

}  // namespace ime_pinyin
